| 摘要 |
PURPOSE:To obtain a servo system of a wide band, by moving an entire actuator means, one side of which moves the optical path in an optical head following up information tracks and the other side of which moves the optical head section in the direction of track, in the direction of the disk width. CONSTITUTION:An actuator which swings a lens system leftward and rightward when electricity is supplied to coils 9 is formed by putting an iron piece around an objective lens 5 which is held by plate springs 7 and 7 and movable leftward and rightward and surrounding the iron piece 8 with a magnetic circuit composed of magnets 9a and 9b. Moreover, voice coils 10 are provided to move the lens system 5 vertically and the coils 10 are used as the actuator of focus servo. On the other hand, a head actuator 11 is put beside a head section 1 so that the head 1 can be moved leftward and rightward with plate springs 6 and 6 as the centers. The actuator 11 is surrounded by another magnetic circuit 13 and the head section 11 is moved by supplying electricity to coils 12. Therefore, the lens 5 can be moved in the direction of disk width by means of the coils 9 and the head section 1 can be moved in the same direction by means of the coils 12. Furthermore, the entire body can be moved in the same direction by means of a motor 14. |
